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    <title>Document</title>
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    <script>
      function changeNum(num1, num2) {
        let temp = 0;
        temp = num1;
        num1 = num2;
        num2 = temp;

        return console.log(`第一个值是${num1},第二个值是${num2}`);
      }

      changeNum(3, 4);
    </script>
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